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Will it freeze in Le Mars in the next 7 nights?
The earliest overnight low at or below 32°F in the available NWS frost forecast is Fri, Nov 6: 31°F (Fri, Nov 6, 6:00 PM CST to Sat, Nov 7, 6:00 AM CST).
Tonight: forecast low 34°F. Frost possible.
NWS forecast period: Thu, Nov 5, 6:00 PM CST to Fri, Nov 6, 6:00 AM CST.
3 of the next 7 nights are forecast at 36°F or colder, cold enough for frost on exposed plants.
- Tonight 34°F Frost possible · Cloudy
- Fri, Nov 6 31°F Freeze · Mostly Cloudy
- Sat, Nov 7 35°F Frost possible · Partly Cloudy
- Sun, Nov 8 39°F Above 36°F · Clear
- Mon, Nov 9 37°F Above 36°F · Mostly Clear
- Tue, Nov 10 39°F Above 36°F · Partly Cloudy
- Wed, Nov 11 40°F Above 36°F · Partly Cloudy
Overnight lows from the National Weather Service forecast for this location. This covers the available forecast window, not the first freeze of the whole season. Frost can form above 32°F on clear, calm nights.
Frost and freeze probabilities
Freeze dates shift from year to year. Spring percentages describe the chance of a freeze after the stated date; fall percentages describe the chance of a freeze by that date. The 10% spring date is the cautious one: a later freeze happens about 1 year in 10.
These dates describe historical probabilities, not this year’s forecast or the earliest and latest possible freezes. Different weather stations or probability thresholds can produce different published dates for the same city.
Average first hard freeze in Le Mars
The median first fall hard-freeze date (28°F) is October 16, from NOAA’s 1991–2020 Climate Normals at Le Mars. This is the 50% probability date, not a forecast for this year.
| Temperature | Last spring date 90% · 50% · 10% chance of a later freeze | First fall date 10% · 50% · 90% chance of an earlier freeze | Season |
|---|---|---|---|
| 36°F frost possible | Apr 28 · May 9 · May 22 | Sep 13 · Sep 27 · Oct 9 | 139 days |
| 32°F freeze | Apr 17 · Apr 30 · May 12 | Sep 21 · Oct 4 · Oct 19 | 157 days |
| 28°F hard freeze | Apr 5 · Apr 20 · May 2 | Sep 29 · Oct 16 · Oct 30 | 178 days |
Average high temperature by month
1991–2020 normals at Le Mars
Average low temperature by month
Months with lows near or below freezing carry frost risk
Where these frost dates come from
The frost dates for Le Mars, IA come from the nearest weather station with freeze statistics in NOAA’s 1991–2020 Climate Normals: Le Mars (station USC00134735, elevation 1,195 ft), 1.4 mi from Le Mars. Local conditions (valleys, hilltops, distance to water, city heat) can shift frost dates by days or weeks. The hardiness zone is from the 2023 USDA Plant Hardiness Zone Map (USDA ARS and Oregon State University PRISM). See our methodology.
Frost dates near Le Mars
| City | Distance | Last spring frost | First fall frost |
|---|---|---|---|
| Orange City, IA | 16 mi | Apr 30 | Oct 3 |
| Sioux Center, IA | 21 mi | Apr 30 | Oct 3 |
| Sioux City, IA | 22 mi | Apr 29 | Oct 7 |
| South Sioux City, NE | 25 mi | Apr 29 | Oct 7 |
| Sergeant Bluff, IA | 28 mi | Apr 29 | Oct 7 |
| Cherokee, IA | 32 mi | May 4 | Oct 4 |
| Sheldon, IA | 32 mi | May 5 | Sep 28 |
| Vermillion, SD | 38 mi | May 3 | Oct 3 |
| Storm Lake, IA | 50 mi | Apr 25 | Oct 13 |
| Harrisburg, SD | 53 mi | May 2 | Oct 2 |
Frequently asked questions
When is the last frost in Le Mars?
On average, the last spring frost (32°F) in Le Mars is around April 30. In about 1 year in 10 it comes after May 12, and in 9 years in 10 it comes after April 17.
When is the first frost in Le Mars?
The first fall frost (32°F) usually arrives around October 4. There’s a 10% chance of a freeze by September 21 and a 90% chance by October 19.
Can it frost in Le Mars after the last frost date?
Yes. Frost can form on clear, calm nights even when the air stays above 32°F. Temperatures of 36°F or lower, cold enough for frost on exposed plants, have a 50% chance of occurring after May 9.
What growing zone is Le Mars?
Le Mars is in USDA Plant Hardiness Zone 5a (average annual extreme minimum temperature −20 to −15°F), based on the 2023 USDA map for ZIP code 51031. See growing zones in Iowa.
More: all Iowa frost dates · Iowa growing zones · frost vs. freeze